Rotary drilling and borehole coring apparatus and method



Jan. 4, 1966 BANNlSTER 3,227,228

ROTARY DRILLING.AND BOREHOLE CORING APPARATUS AND METHOD Filed May 24,1963 6 Sheets-Sheet 2 C/ ya e 150/7)? fer INVENTOR.

A Trek/v5 VJ Jan. 4, 1966 c, BANNISTER 3,227,228

ROTARY DRILLING AND BOREHOLE CORING APPARATUS AND METHOD Filed May 1963e Sheets-Sheet s P/FEJJ ums PREJJURE PUZ JE PUL JE GENERATOR GENERATOR30 M A /d/ THRESHOL 0 L/M/TER $2 20 l w/ wam me J TEPPl/VG /fl6 JW/TCH h/05 1 C/yc/e .5. 50/7/70 fer INVENTOR BY Mam e- Jan. 4, 1966 c. E.BANNISTER 3,227,223

ROTARY DRILLING AND BOREHOLE GORING APPARATUS AND METHOD Filed May 24,1963 6 Sheets-Sheet 5 BY M ATTOIP/Vfyj 1966 A c. E. BANNISTER 3,

ROTARY DRILLING AND BOREHOLE CURING APPARATUS AND METHOD 6 Sheets-Sheet6 Filed May 24, 1965 I V m C/yc/e E. 5000/: fer

INVENTOR.

United States Patent Filed May 24, 1963, Ser- No. 283,023 16 Claims.(Cl. 175-4) This invention pertains to the improvement of subsurfacedrilling techniques and more especially to novel apparatus and methodfor sampling the formation (frequently called coring) in a boreholedrilled with a rotary r1 g The prior art techniques are well known andwill be considered just briefly to point up the unsual significance ofthe invention.

It is conventional practice in certain localities to sample a formationat different levels in a borehole to ascertain the proximity of an oilbearing formation. The borehole is drilled by a rotary rig, a term usedherein to describe a drill assembly having a drill string comprisingdrill pipe, drill collars, a bit, and apparatus for rotating the drillstring in one direction during the drilling operation. Drill mud ispumped through the drill string and circulated upwards, around the drillstring, to wash out cuttings, and is maintained at a relatively heavyweight to prevent borehole cave-ins. When samples of the formation aredesired the drill string is removed and a side-wall sampling tool thedrill string. The mud circulation is stopped and the kelly is removed togain access to the drill pipe central passage. Obviously, the selectionof cutting bits is limited if core samples have to be taken in thismanner and cores can only be taken from the bottom of the bore hole.

Recognizing the continued importance of formation sampling, I havedevised an invention with the object of taking cores without theinconvenience of the time honored coring techniques used with rotarydrilling. The drill string need not be removed from the hole and coresamples can be taken at any level without interfering with the drillingoperation. There is no need to use a special drill bit, leaving theoperator free to make his choice based on performance. And, certainlynot last by any means, a cable is not required to control the taking ofcores.

My invention also includes a coring device having general utility whichis an improvement over the device described and claimed in my UnitedStates Patent 2,717,760; The sample-taking projectile will shoot-back,i.e., return to the barrel or casing, irrespective of how far theprojectile enters the formation, making the coring device useful in alltypes of formations.

These and many otherobjects and advantages of my invention areaccomplished in one embodiment by having one of the drill collars(hereinafter called a coring collar) in the drill string of a rotary rigcontain a plurality of sample-taking devices and means for firing thedevices in response to a remotely located wave energy source. The. waveenergy can be a controlled vibration of the drill string, a radio wavetransmission, or a pressure variation transmitted down the drill mud. Mymethod offdrilling and coring in one form involves inserting the unitmounting the coring devices and remotely controlled firing means inthedrill string adjacent the bit, disposing the drill string intheborehole, and commencing rotary operation of one or more coring devicesis selectively controlled by wave energy transmission from a remotelocation.

The improvement of my coring device includes in one embodiment thearrangement of the second explosive means (the one that providespositive shoot-back) on the sample-taking projectile and the provisionof means on the projectile to fire the second explosive means at apredetermined time after the explosive means fires.

A description of my invention commences herewith, reference being madeto the attached drawings, wherein:

FIG. 1 is a part schematic and part pictorial presentation of aconventional rotary drilling rig showing three Ways of remotelycontrolling the firing of coring devices in a coring collar.

FIG. 2 is an elevation sectional view showing partially in schematicform a coring collar having coring devices and remotely controlledfiring means mounted therein. FIG. ,3 is an elevation sectional viewtaken along the lines 3-3 of FIG. 1, illustrating one form of vibratorfor vibrating a drill string to remotely control the firing of thecoring devices in a coring collar.

FIG. 4 is a horizontal sectional view taken along the lines 4-4 of FIG.2, illustrating one arrangement for locating the firing means in acoring collar.

FIG. 5 is a fragmentary, elevation sectional view of one type of drillstring vibration responsive firing means mounted with coring devices ina coring collar.

FIG. 6 is a fragmentary, elevation sectional view of one type ofpressure responsive firing means mounted with coring devices in a coringcollar.

FIG. 7 is a fragmentary, elevation sectional view of another type ofpressure responsive firing means mounted with coring devices in a coringcollar. FIG. 8 is a schematic representation of a radio transmitter forfiring coring devices and a fragmentary, elevation sectional view of aradio wave responsive firing means mounted with coring devices in acoring collar.

FIG. 9 is a horizontal section of one form of my improved coring device,taken along the lines 9-9 of FIG. 2, and illustrating the arrangement ofparts in the normal, firing position.

FIG. 9A is an enlarged view of the locking means on the reaction membershown in FIG. 9.

FIG. 10 is a horizontal section of the coring device illustrated in FIG.2, taken along the same section lines a as FIG. 9, with the parts shownin the position after cordrilling. When a formation sample is to betaken the ing and before shoot-back.

FIG. 11 is a horizontal section, as FIGS. 9 and 10 with the coringdevice parts shown in their position after shoot-back.

FIG. 12 is a horizontal section of another coring device suitable foruse in a coring collar, illustrating the arrangement of parts beforefiring of any explosive.

FIG. 13 is a horizontal section of the same coring device as illustratedin FIG. 12, showing the arrangement of parts during ejection of theplug.

FIG. 14 is an enlarged View of the check valve shown in FIGS. 12 and 13.

The figures use block diagrams and schematic representations to simplifythe presentation of the electrical aspects of my invention. In each sucharrangement it must be recognized that several types of apparatus can beused, the ones suggested being merely examples of preferred typesreadily available to one skilled in the art to perform the desiredfunction. Further, it is apparent to one skilled in the art that themechanical apparatus can take several forms and still carry out thedesired function.

In applying my invention any rotary rig can be used, such as theconventional one identified by reference numeral 1 in FIG. 1, thatincludes derrick 2 from which travel- Patented Jan. 4, 1966 ing block 3is suspended, and swivel 4 pivotally connected to traveling block 3 andreceiving hose 5 that carries the drill mud 6 from standpipe 7 to drillstring 8 through kelly 9. Drill string 8 is composed of drill pipe 10and drill collars 11 and a bit 12 is attached at the lower end. Thedrilling action is the result of the drill string weight applied to thebit 12 as the drill string 8 rotates in one direction in rotary table 13motivated by a prime mover (not shown). The cuttings are removed fromthe borehole 14 by the drill mud 6 circulated by a mud pump (not shown)connected at inlet pipe 15 and exhausted from the casing 16 at outletpipe 17.

The above thumbnail description of a rotary rig is sufficient forintroducing my invention, reference being made to the numerous texts andarticles on this subject for the more specific details of the operationand apparatus connected with a rotary rig.

As mentioned previously, it is very important under some circumstancesto take samples of the formation in the borehole 14. The conventionalpractice is to remove the drill string 8 piece-by-piece, stacking it,and lowering a coring tool, generally referred to as a side-wallsampler. A day or more can be consumed each time to take the samples andresume drilling, so that samples are not taken until the need isdefinitely apparent and only after a considerable length of borehole hasbeen drilled. Alternatively, a special coring bit is used and the coreis manipulated up from within the drill string by a wire line.

In my invention, the cores can be taken by a coring collar 20 in thedrill string 8. The coring collar 20 mounts a number of coring devices21 that are fired by a firing selector 22 (FIG. 2) controlled by waveenergy transmitted from a wave energy source at the surface to areceiver 23 located in coring collar 20. The coring devices 21 can befired selectively at any desired formation level.

The coring collar 20 has many of the characteristics of the conventionaldrill collar, being located adjacent the bit 12, having a centralpassage for the flow of drill mud 6 to hit 12, and tool joints 31 and 32at the ends to connect between two drill collars, or to a drill collar11 and the bit 12 as shown in the disclosed embodiment of FIG. 1. Thereceiver 23 and firing selector 22 can be stored in coring collar 20 ina number of ways, such as in body recesses covered with plates 33, asillustrated in FIG. 4, fastened to provide a water tight closure. Thelength of the coring collar 26 can be the standard 30 feet for a drillcollar, allowing ample room to house many coring devices 21 and theremotely controlled firing apparatus.

The details of the illustrated improved coring device will be describedlater, but other types of coring devices can be used in the coringcollar 20. For example only, the coring device describd in my UnitedStates Patent 2,717,760 can be employed. No matter what type of coringdevice is used, each performs the function of moving a sample-takingprojectile into the formation to take a core that can be recovered atthe surface for analysis. In the illustrated embodiment, coring device21 has the valuable feature of retrieving the core into the coringcollar 20.

The compatibility of my invention to the rotary drilling technique isimmediately apparent. A coring collar 20 is inserted in the drill string8, lowered with the bit 12, and drilling commences. When a core isdesired, one or more of the coring devices 21 is fired and the drillingcontinues. Enough coring devices can be incorporated in the coringcollar 20, or in additional coring collars, to take all the coresdesired until the drill string has to be removed for other reasons.Since a bit usually needs replacement every 24 hours or so, the coringcollar 20 can be replaced with another coring collar at that time andthe cores are neatly collected for analysis.

The coring devices 21 can be fired by several forms of controlled waveenergy originating from wave energy sources at the surface. The waveenergy can be a vibration transmitted down the drill string 8 from avibration wave energy source (FIG. 1), a pressure variation from apressure wave energy source 41, or an electromagnetic transmission froma radio wave source 42. Each of these wave energy sources isconveniently associated with a rotary rig without interfering orsignificantly delaying the operation, as will be described hereinafter.

The vibration wave energy source 40 makes use of the fact thatmechanical vibration travels quite readily along a hard body, such asdrill string 8. The vibration can have a distinctive characteristic toprevent external vibrations from duplicating the vibration and firingthe coring devices 21. For example, this characteristic can be thevibration frequency, selected to avoid any natural or harmonic vibrationfrequencies of the rig apparatus. Different frequencies can be used tofire each coring device. Alternatively, transmission of a vibrationpulse can successively fire the coring devices.

One typical embodiment of a mechanical vibratory system for firing thecoring devices 21 is illustrated in FIGS. 1, 3, and 5. The vibratorywave energy source 40 includes an A.C. generator that has a variablefrequency capability, with a range of 5000 to 20,000 c.p.s., forexample. The A.C. signal from the generator 45 is amplified in AC.amplifier 46 and coupled to a vibrator 47 attached to kelly 9. Themechanical vibrations in the drill string 8 are sensed by a transducer48, preferably of the piezoelectric type, mounted by bracket 4-9 againstwall 50. The transducer output is coupled through an amplifier 53 to afilter 51 having a separate band-pass filter channel and output for eachof the frequencies selected to operate the coring devices. When avibration at one frequency is transmitted, the filter channel and outputcorresponding to that frequency produces a sufiicient signal to fire anelectric detonator (to be pointed out later) on one coring device, thesignal being carried over a separate conductor of output cable 52 to therespective coring devices 21.

The vibrator 47 is illustrated in detail in FIG. 3, wherein a frameformed by two arms 55 and 56 pivotally attached by pin (like a pair ofpliers) is clamped against kelly faces 65, 66 and 67 and secured bylocking bolt 57. Arm 55 is bent to provide an inner space beside kellyside 71 for an armature plate 58, pivotally mounted at one end 62, thatvibrates at the frequency of the AC. signal applied to coil 59 wrappedon post 61. A closed magnetic circuit is formed by cup 60 fixed to arm55 and centrally fixed post 61, both of ferromagnetic material, to drawarmature 58 upward, as viewed in FIG. 3, against the force of a spring63. The armature 58 carries a striker 64 of a hard metal that sets upthe vibrations in kelly 9. By disengaging the bolt 57 the arms 55 and 56can be spread apart to easily and quickly remove vibrator 47.

Any one of coring devices 21 is fired simply by setting generator 45 tothe appropriate frequency and closing switch 40 to connect the generator45 to vibrator 47 The corresponding filter channel and output in coringcollar 20 is energized to fire the associated coring device 21. Asquelch or other limitingv circuit can be incorporated following thefilter output to prevent firing of the coring device 21 unless a givenvibration intensity is received at the coring collar 20.

The coring devices can be fired by a pressure vibration having adistinctive characteristic transmitted down the drill mud 6. A pulse ora wave having a preset frequency can select which coring device is to befired.

One embodiment of a pressure pulse firing system is illustrated in FIGS.1 and 6. The pressure pulse source 41 fires an explosive charge 75 whenswitch 76 is closed in a fluid filled explosion chamber 77 connectedthrough valve 78 to the standpipe 7. Drill mud circulation is stopped,normally closed valve 78 is opened and normally opened valves 79 and- 85in the inlet and outlet pipes 17 and 15, respectively, are closed. Theexplosion creates a steep front, high amplitude pressure variation thattravels down the drill mud 6 inside drill string 8 to the coring collar20.

Disposed within coring collar 20 is a pressure responsive receivingmeans 80 (FIG. 6) that actuates a firing selector 81 to selectively firethe coring devices 21. The pressure variation flexes a diaphragm 94disposed in the wall of passage 30, transmitting a force through anincompressible fiuid 82 to apiston 83. An outward force (to the left asviewed in FIG. 6) is applied to piston 83 by a spring 84 keeping contact86 at the endof piston rod 37 from stationary contact 88. When the highamplitude pressure variation reaches the coring collar 20, the contacts86 and 88 close an energizing circuit including battery 89 to a solenoid96 that operates a pawl 90 and rotates a ratchet wheel 91 to a newposition. At each position of ratchet wheel 91 an attached contact arm92 connects with a fixed contact that closes an energizing circuitincluding battery 93 to fire the electric detonator in one of coringdevices 21. Each pressure pulse fires another one of coring devices 21as the ratchet wheel 91 is progressively moved to new positions.

Another form of pressure responsive receiving means that uses electronictechniques to duplicate the above described electromechanical system'isillustrated in FIG. 7. The present day miniaturization of electroniccomponents facilitates the compact arrangement of this apparatus,wherein the pressurevariation is sensed by a pressure responsivetransducer 100, preferably a piezoelectric device, and a voltageproportional to the pressure, after being amplified by amplifier 101, iscoupled to a threshold limiter 102. The thresholdlimiter 102 serves toprevent normal pressure variations in the drill rnud 6 from firing thecoring devices 21 by producing an output signal only if thepressure-proportional input voltage exceeds a preset minimum. A Schmidttrigger circuit is one suitable type of threshold limiter, producing foreach input pulse about a preset level an output pulse that is coupled toa univibrator 107 (a mono-stable multivibrator) to produce a pulse thatis amplified in amplifier 103. Each pulse activates a stepping switch104 having an input to successively connect an input 105 to each ofoutputs 106, closing an energizing circuit including battery 108 for theelectric detonator'of one of the coring devices 21.

It is apparent that the vibration wave system previously described canbe modified to operate on a series of pulses as in the pressureresponsive system embodiment just described with reference to FIG. 7. Insuch an arrangement only one frequency need be used and the A.C.generator 45 would be connected to vibrator 47 only for a moment toproduce each vibratory pulse. The vibration response receiver wouldinclude a band-pass filter preferably following amplifier 101 thatresponds only to the selected frequency.

Another pressure wave firing system suitable for use in the presentinvention utilizes a pressure source that generates an alternatingpressure variation at a single frequency in the drill mud 6. Thepressure wave responsive receiver includes a pressure variationtransducer that produces an A.C. signal from the transmitted pressurewave, using a filter channel to fire one of the coring devices. As inthe mechanical vibration arrangement, other frequencies and filterchannels can be incorporated to selectively fire additional coringdevices 21. l

The coring devices 21 can be fired selectively using electromagneticwave radio energy transmitted through i the earth to the coring collar20. A pulse system, similar to the arrangement for the pressure waveenergy system can be used, wherein a suitable radio receiver is mountedin coring collar 20 to activate a stepping switch. Alternatively, theradio wave can be modulated with signals that operate receiving means inthe coring collar to select and fire different coring devices.

One typical embodiment of a modulated radio wave system is illustratedin FIG. 8, wherein a carrier, produced by radio frequency generator ismodulated with a single frequency audio signal from audio signalgenerator 121 by modulator 122. The modulated carrier is radiated byantenna 123, and picked up by radio receiver 124 in receiving antenna127 in coring collar 20. The receiving antenna 127 can be embedded in aplastic insert in plate 33 and appropriately loaded to suificientlymatch for the range of frequencies being used, for example, lowfrequencies in the range of 15 to 30 kilocycles, or higher frequencies.After demodulation of the received signal the audio frequency isselected by a separate band-pass channel in filter 125 and coupled to aseparate firing channel in control device 126 and thence to an electricdetonator on one of the coring devices 21. Each control device channelhas a relay (not shown) that is activated by the received audio signalto closea battery activated firing circuit. With each of coring devicesresponding to a different modulated audio signal, the coring devices 21can be selectively fired.

One embodiment of my improved coring device, illustrated in FIGS. 9through 11, has the advantage of positive shoot-back of thesample-taking projectile. When used with the aforementioned coringcollar 20 the cores are retrieved and conveniently stored until thedrill string is removed.

In my prior form of coring device, described in United States Patent2,717,760, a second explosive mounted in the barrel or casing at theopposite end from the first explosive shoots the sample-takingprojectile back. The firing of the second explosive is dependent on thesampletaking projectile moving at least a given distance into theformation to ignite a powder train housed in the casing. In especiallyhard formations the projectile may not have a sufiicient distance, eventhough an adequate sample is taken, to fire the second explosive. And,even if the projectile moves far enough to just fire the secondexplosive, a large chamber volume is present, diminishing the initialshoot-back force on the projectile. 1

'In accordance with my improved coring device, the

second explosive means and means for firing same at a predetermined timeafter the first explosive fires are carried by the sample-takingprojectile. No matter how far the projectile moves the second explosiveis fired and exerts a substantial shoot-back force. With specificreference to FIG. 9, one embodiment of my improved coring device 21 ismounted in coring collar 20 disposed in borehole 150. The coring devicecasing 151 is annular, having one end 152 that firmly seats in an insidewall recess 155 of coring collar 20 and an opposite end 156 threaded toengage with mating threads 153 in the wall of coring collar aperture154, thereby providing easy access for removal of the coring device 21.The coring device casing 151 is constructed of a heavy metal and ofsufiicient size to prevent expansion due to the explosions therein.

Disposed'within coring device casing 151 is the sampletaking projectile160 having cylindrical head 161 and a narrower cylindrical body 162extending axially through and supported by an annular plug 163 threadedinto the opening at casing end 152. A suitable seal, such as O- ring164, between the body 162 and plug 163 prevents drill mud 6 fromentering. Samples are taken by the hollow end 165 of body 162, which isclosed by a plug 166 to prevent drill mud 6 from entering butsufficiently flexible to bend inwardly and to be forced into theprojectile hollow with the formation sample (see FIG. 11), as air orfluid therein escapes through ports 167. Air or fluid can pass only outfrom the hollow of body 162 through ports 167 due to check valves 250composed of a fiat spring 253 attached at one end in a recess 252 byfastener 254. Coring collar 20 has an aperture that receives the 7 bodyend 165 and allows movement into a formation. Movement of projectilehead 161 past the check valves 210 is prohibitedby a lock ring 211retained in a slot in the inner casing wall just adjacent the checkvalves 210 and after lip 191.

The projectile 160 is propelled into the formation by a packaged chargeof explosive 170 disposed in the closed casing end 156 adjacent head161, the explosive 170 being fired by an electric detonator 171activated with a current received over cable 172 recess mounted in theouter wall of coring collar 20. Air or fluid forward of the head 161escapes through check valves 210 in ports 183 at the casing end 152 thatallow fluid to flow out but not into casing 151.

The check valves 210 can be of several conventional constructions. FIGS.9 and 14 illustrate the details of one form of suitable check valve andthe other figures show the check valves 210 in schematic form.

Fluid from within casing 151 moves a pop valve member 216 away from aseat 217 threaded in part 183. The valve member 216 is supported in aspider 218 threaded in part 183 and having ports 219 for the fluid topass through. A closing force provided by a helical spring 215 holdsvalve member 216 against seat 217 to prevent fluid from outside casing151 from passing into casing 151.

When explosive 1'70 is fired, vent ports 173 in casing end 156 areclosed by an annular sleeve 174 axially disposed within casing 151 aboutprojectile 169, as shown in FIG. 9, and a tight gas seal is provided bysuitable means, such as O-ring 175 in the outer circumference of head161. The aforementioned parts in coring device 21 take the positionshown in FIG. after the explosive 171i is fired.

The projectile 161) carries an annular packed charge of explosive 177immediately adjacent the opposite side of head 161 from explosive 170,which is fired by a delay fuse 178, such as an impregnated cloth orblack powder train, being ignited at one end by the explosion ofexplosive 170 and firing explosive 177 at a predetermined time later.

The projectile 160 also carries an annular reaction member 180 thatmoves with projectile 160 in the forward direction but is slidable onbody 162 and relative to sleeve 174, with a gas seal provided by O-rings181, to allow the reaction member 180 to move separately relative tosleeve 174 and projectile 160 after explosive 177 is fired.

Reaction member 180 includes a locking means 184 composed of separatepins 18? that slide freely in radial passages 187 (see FIG. 9A) openingto sleeve 174 and having tapered heads 185 (see FIG. 9A) that can engagein circumferential slots 186 in the inner wall of sleeve 174. As shownonly in FIG. 9A, the passages 187 have tooth-shaped walls 195 arrangedto permit free radial outward movement of a pin attached flexible washer188 but to prevent rearward movement, thereby firmly locking the pins189 to sleeve 174.

After the predetermined time delay controlled by delay fuse 178, theprojectile 160 will be in some forward position, such as shown in FIG.10, the explosive 177 fires and forces reaction member 180 towardscasing end 152. Explosion gases enter through separate ports 19!) to acton the rear of each of pins 189, forcing them radially outward, and veryquickly lodging them firmly in one of sleeve slots 186. Then sleeve 174moves a small distance towards casing end 152 to engage a lip 191 in theinner wall of casing 151, aligning sleeve ports 196 with vent ports 173at casing end 156, permitting the gases from the explosion to escape.The reaction member 180 cannot move further in the direction of casingend 152 and the explosive gases force projectile head 1 61 rearward,towards casing end 156, withdrawing the projectile body 162 from theformation.

FIG. 11 illustrates the position of the coring device parts after theprojectile with the core therein has been retrieved.

Another embodiment of my improved coring device is 8 shown in FIGS. 12,1-3 and 14. In this arrangement the number of parts is reduced and thegases from the first explosive are exhausted from a port, irrespectiveof how far the projectile moves, by opening the port at a predeterminedtime after the explosion of the first explosive.

Several of the parts are the same as in the embodiment shown in FIGS. 9through 11 and bear the same reference numerals.

The sleeve 174 is eliminated and the projectile fits slidably within thecasing 151, O-ring 175 sealing the head 161 against the inner casingwall. The projectile 160 carries the explosive 171 and locking means 184as described previously in detail, the slots 186 being in the inner wallof casing 151.

Gases are vented from within casing 151 through oneway check valves 200during the forward movement of projectile 160. The gases from theexplosion of explosive are exhausted by blowing out a conical frustrumshaped metal plug 291 disposed in tapered port 205 in casing end 156with the larger diameter side facing within casing 151. The plug 201 issurrounded by a packaged ring of explosive 2 02 disposed in acircumferential groove 215 and connected to one end of delay fuse 203.The opposite end of delay fuse 203 connects with explosive 171) and isignited at the same time. Plug 201 has an eccentric outer lip 20 thatcauses plug 261 to travel out of alignment with the port 265, reducingthe possibility that the lug 291 will be reinserted as the projectile16%) moves rearward during shoot-back.

The time relation of the explosions is controlled by the delay fuses 178and 203. The explosive 170 fires and ignites one end of delay fuses 178and 203. After a predetermined time period the explosive 202 fires,ejecting plug 201. The projectile 160 may have completed taking a sampleby that time. Next, the explosive 171 fires, shooting the projectile 160back, as the gases from explosive 170 escapes out of port 205. Thus, thetime delay of fuse 203 is shorter than fuse 178.

The locking means 184 functions as described previ ously, the onlydifference being that the slots 184 are in casing 151 and pins 189 lockreaction member 189 and casing 151 together.

The disclosed embodiments of my invention are presented merely asexamples of suitable apparatuses and methods. Changes, modifications andother embodiments arranged in accordance with the teaching of myinvention are part of my claimed invention as defined in the appendedclaims.

What is claimed is:

1. A well drilling and core sampling mechanism, comprising,

a rotary rig including a drill string having a cutting bit and drillcollars at one end,

a coring collar in said drill string having mounted therein a pluralityof sample-taking devices and means for firing said devices,

said firing means comprising a receiving means responsive totransmission of wave energy from a remote source to selectively firesaid devices, source means to be disposed at a remote location forproviding transmission of said wave energy.

2. Apparatus as described in claim 1, wherein,

said source means produces wave energy which is a substantial pressurevariation transmitted through the drill mud to said receiving means thatresponds to said pressure variation to fire at least one of saiddevices.

3. Apparatus as described in claim 1, wherein,

said source means produces wave energy which is a mechanical vibrationcoupled to said drill string to which said receiving means responds toactuate at least one of said devices.

4. Apparatus as described in claim 1, wherein,

said Source means produces wave energy which is a radio transmission towhich said receiving means responds to actuate at least one of saiddevices.

5. Apparatus as described in claim 1, wherein,

said source means produces wave energy which is a pressure pulse set upby exploding a charge in the drill mud and said receiving means includesa pressure sensitive means that actuates a stepping switch means tosuccessively fire said devices.

6. Apparatus as described in claim 1, wherein,

said source means produces wave energy which is a radio transmissionhaving selected modulation frequencies that energize said receivingmeans to fire difierent ones of said devices.

7. Apparatus as described in claim 1, wherein,

said source means produces wave energy which is a mechanical vibrationof a selected frequency that is transmitted down the drill string tosaid receiving means that includes a frequency sensitive meansresponsive to said mechanical vibration to fire at least one of saiddevices.

8. A well drilling and core sampling mechanism, comprising,

a rotary rig including a drill string having a cutting bit and drillcollars at one end,

a coring collar in said drill string having a plurality of sample-takingdevices including means that retrieve the core sample into said coringcollar, and

means in said coring collar for selectively firing said devices inresponse to a remotely located wave energy source,

source means to be disposed at a remote location for providingtransmission of said wave energy.

9. The apparatus as described in claim 8, wherein,

said coring devices are propelled outward and retrieved by explosivecharges.

10. The apparatus as described in claim 8, wherein,

said source means produces wave energy which is a pressure variationtransmitted through the drill mud.

11. The apparatus as described in claim 8, wherein,

til

said source means produces wave energy which is a radio transmission.

12. The apparatus as described in claim 8, wherein,

said source means produces wave energy which is a mechanical vibrationtransmitted down the drill string.

13. A method of taking samples from a borehole wall,

comprising the steps of,

inserting a unit having a number of coring devices in the drill stringof a rotary rig,

disposing said drill string in the borehole,

commencing drilling in said borehole,

initiating operation of the core devices at desired levels by controlledwave. energy transmission from a remote location.

14. The method as described in claim 13, wherein,

selective initiation of said coring devices is controlled by radiotransmission.

15. The method as described in claim 13, wherein,

selective initiation of said coring devices is controlled by pressurevariation transmitted through the drill mud.

16. The method as described in claim 13, wherein,

selective initiation of said coring devices is controlled by vibrationtransmitted down the drill string.

References Cited by the Examiner UNITED STATES PATENTS Re. 20,120 9/1936Schlumberger l-4 1,757,288 4/1930 Bleecker 10221 X 2,304,408 12/1942Holifield 16655.4 2,356,082 8/1944 Otis 16635 2,408,419 11/1946 Foster-4 X 2,761,385 9/1956 Schlumberger 1754 2,917,280 12/1959 Castel 17553,016,959 l/1962 Berthelin 175-4 3,072,202 1/ 1963 Brieger 175-4 CHARLESE. OCONNELL, Primary Examiner.

BENJAMIN HERSH, Examiner.

1. A WELL DRILLING AND CORE SAMPLING MECHANISM, COMPRISING, A ROTARY RIGINCLUDING A DRILL STRING HAVING A CUTTING BIT AND DRILL COLLARS AT ONEEND, A CORING COLLAR IN SAID DRILL STRING HAVING MOUNTED THEREIN APLURALITY OF SAMPLE-TAKING DEVICES AND MEANS FOR FIRING SAID DEVICES,SAID FIRING MEANS COMPRISING A RECEIVING MEANS RESPONSIVE TOTRANSMISSION OF WAVE ENERGY FROM A REMOTE SOURCE TO SELECTIVELY FIRESAID DEVICES, SOURCE MEANS TO BE DISPOSED AT A REMOTE LOCATION FORPROVIDING TRANSMISSION OF SAID WAVE ENERGY.
 13. A METHOD OF TAKINGSAMPLES FROM A BOREHOLE WALL, COMPRISING THE STEPS OF, INSERTING A UNITHAVING A NUMBER OF CORING DEVICES IN THE DRILL STRING OF A ROTARY RIG,DISPOSING SAID DRILL STRING IN THE BOREHOLE, COMMENCING DRILLING IN SAIDBOREHOLE, INITIATING OPERATION OF THE CORE DEVICES AT DESIRED LEVELS BYCONTROLLED WAVE ENERGY TRANSMISSION FROM A REMOTE LOCATION.